Results 31 to 40 of about 55,649 (206)
Odessa Astronomical Publications, 2017 The main parameters of the close binaries V448 Cyg and XZ Cep were determined. Computation of the chemical composition of the atmospheres of their primary components showed the existence of the hydrogen deficiency in them.
L. V. Glazunova, G. V. Manilova
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Magnetic fields in circumstellar envelopes of evolved AGB stars [PDF]
, 2019 In this paper, a time-dependent magnetohydrodynamic model is presented which aimed at understanding the superwind production by an evolved AGB star and the consecutive formation of a dense circumstellar envelope around it. We know henceforth from various
Pascoli, Gianni
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Molecules in Circumstellar Envelopes [PDF]
Highlights of Astronomy, 1989 ABSTRACTThe chemistry of circumstellar envelopes around evolved stars is extremely rich, especially for C-rich ones. 34 molecules have been identified in IRC+10216. Recent observations and modeling prove that most of the unstable species are formed by photochemistry in the outer layers of the envelope.
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MODELS OF CIRCUMSTELLAR MASERS IN BIPOLAR OUTFLOWS
Odessa Astronomical Publications, 2017 Sources of molecular maser radio emission in envelopes of late-type variable stars (red giants and supergiants) are considered. Radio and optical data on asymmetry of mass loss process in red giants are briefly reviewed.
G. M. Rudnitskij
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The Astrophysical Journal, 2023 We obtained accurate vibrational frequencies, rotational constants, and vertical transition energy for AlNH _2 (X ^1 A _1 ) and HAlNH(X ^1 A′) isomers using ab initio calculations at various levels of theory.
Tarek Trabelsi +2 more
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Infrared spectroscopy and molecules in circumstellar envelopes [PDF]
International Astronomical Union Colloquium, 1994 During the last two decades there has been a tremendous renewal of interest in the circumstellar environment of evolved stars. This renewal has been mainly driven by sensitive microwave observing techniques. Microwave spectroscopy has resulted in a number of fundamental discoveries in circumstellar shells, including the discovery of maser lines and ...
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Astronomy & AstrophysicsAims. We present the largest catalogue of asymptotic giant branch (AGB) stars, 45 targets in total, observed in polarized light at high angular resolution (~20 milliarcsec).
Badolo Nekolgne Aymard +9 more
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Circumstellar Envelopes of OH-IR Sources [PDF]
Symposium - International Astronomical Union, 1987 This article reviews recent radio observations of maser emission from OH, H2O and SiO molecules in the circumstellar envelopes of OH-IR sources. The different radio lines require different conditions for their excitation, and each therefore probes different regions in the circumstellar envelope. For some stars radio interferometer maps of several maser
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CO line emission from circumstellar envelopes
, 2006 Aims.We present the results of a multi-transition CO observational program conducted on a sample of AGB and post-AGB stars envelopes. We have collected maps and single pointing observations of these envelopes in 5 rotational transitions ranging from J
Phillips, T. G. +9 more
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Millimetre Observations of Maser-Emitting Planetary Nebulae
Galaxies, 2022 Observations in the millimetre bands of maser-emitting planetary nebulae (PNe) are crucial to study their circumstellar molecular gas at the beginning of the PN phase.
Lucero Uscanga +9 more
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